1. Field of the Invention
This invention relates generally to a cord lock and release system for a window blind assembly. More particularly, the invention relates to a cord lock and cord release system capable of being actuated independent of the positioning of the cords.
2. Description of the Prior Art
Window blind assemblies are typically operated by having one or more lift cords being connected at one end to the window blinds and having the other end which extends out of the blinds being accessible to the operator. The window blinds are typically raised by the operator pulling on the accessible portion of the lift cords and are lowered by allowing the weight of the shade to pull the lift cords back into the blind. When the operator has moved the blind to a desired position, the lift cords must be held in place so that the blind will remain in the chosen position after the operator has let go of the lift cords. For this reason, the art has developed various types of cord locking devices. Some cord locks such as those disclosed in U.S. Pat. No. 4,443,915 to Niemeyer employ a cam-like tumbler and others such as those shown in U.S. Pat. No. 4,660,612 to Anderson have a jaw-like cord lock structure. To operate these types of cord locks, some secondary movement of the lift cords other than in and out of the blind is required. For example, to lock and to unlock the device of Niemeyer, the operator must move the lift cords transversely either upwards or downwards across an inclining surface. In order to operate the device of Anderson, the operator must move the lift cords away from the plane of the blind assembly. Often, because of the location of the blind assembly in a room or because of furnishings in the room, movement of the lift cords in the manner required in the prior art is very difficult. It is also confusing to the operator because different products might require different secondary movements of the lift cords as in the above examples and it is not obvious to the operator which motion is correct.